IEC 62341-6-1:2022

IEC 62341-6-1 ®
Edition 3.0 2022-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Organic light emitting diode (OLED) displays –
Part 6-1: Measuring methods of optical and electro-optical parameters

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IEC 62341-6-1 ®
Edition 3.0 2022-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Organic light emitting diode (OLED) displays –
Part 6-1: Measuring methods of optical and electro-optical parameters
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.260 ISBN 978-2-8322-5895-8

– 2 – IEC 62341-6-1:2022 RLV © IEC 2022
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
4 Structure of measuring equipment . 8
5 Standard measuring conditions . 9
5.1 Standard measuring environmental conditions . 9
5.2 Standard measuring dark room conditions . 9
5.3 Standard setup conditions . 9
5.3.1 General . 9
5.3.2 Adjustment of OLED display modules . 9
5.3.3 Starting conditions of measurements . 9
5.3.4 Measuring equipment requirements . 9
5.4 Standard locations of measurement field. 12
5.5 Standard test patterns . 12
6 Measuring methods for optical parameters . 18
6.1 Primary luminance, colour, and uniformity of full-colour high-resolution
modules . 18
6.1.1 Purpose . 18
6.1.2 Measuring conditions . 18
6.1.3 Measuring methods for high-resolution full-colour modules . 18
6.1.4 Maximum luminance of white and RGB primaries . 20
6.1.5 Average colour of maximum white and RGB primaries . 20
6.1.6 Luminance uniformity of white and RGB primaries . 21
6.1.7 Colour non-uniformity of maximum white and RGB primaries . 21
6.1.8 Colour additivity of maximum white and RGB primaries . 22
6.1.9 White correlated colour temperature . 22
6.2 Primary luminance, colour, and uniformity of low-resolution modules . 22
6.2.1 Purpose . 22
6.2.2 Measuring conditions . 23
6.2.3 Measuring methods for low-resolution modules and segmented displays . 23
6.3 Signal loading . 23
6.3.1 Purpose . 23
6.3.2 Measuring conditions . 23
6.3.3 Measuring methods . 23
6.4 Dark room contrast ratio . 24
6.4.1 Purpose . 24
6.4.2 Measuring conditions . 24
6.4.3 Measuring method . 24
6.5 Display colour gamut, colour gamut area, and colour gamut volume . 25
6.5.1 Purpose . 25
6.5.2 Measuring conditions . 25
6.5.3 Measuring methods . 25
6.5.4 Display colour gamut . 25

6.5.5 Display colour gamut area in the CIE 1976 chromaticity diagram . 26
6.5.6 Colour gamut volume . 26
7 Measuring methods for power consumption . 28
7.1 Purpose . 28
7.2 Measuring conditions . 28
7.3 Measuring methods . 28
7.3.1 Measuring the power consumption relevant to luminance of the OLED
display module without a signal decoding process . 28
7.3.2 Measuring the power consumption of the OLED display module’s

embedded video connection terminal with a signal decoding process . 30
Annex A (normative) Response time of passive matrix display panels . 33
A.1 Purpose . 33
A.2 Measuring conditions . 33
A.3 Measuring methods . 33
Annex B (normative) Luminance current efficiency . 35
B.1 Purpose . 35
B.2 Measuring conditions . 35
B.3 Measuring methods . 35
Annex C (informative) Veiling glare frustum . 37
Annex D (informative) Methods to obtain the correlated colour temperature (CCT) from
chromaticity coordinates . 38
D.1 Method 1: Use of McCamy’s approximate formula . 38
D.2 Method 2: Use of Javier Hernandez-Andres’s approximate formula . 38
D.3 Method 3: Graphical determination of correlated colour temperature . 39
Annex E (informative) Measuring performance of modern colour-managed displays

and panels . 42
E.1 Legacy displays . 42
E.2 Modern displays . 42
E.3 Results . 44
E.4 Conclusion . 49
Annex F (informative) Simple window luminance and colour measurements . 50
F.1 Background. 50
F.2 Measuring conditions . 50
F.3 Maximum full screen luminance . 50
F.4 4 % window luminance . 50
F.5 Sampled luminance non-uniformity . 50
F.6 4 % window centre colour . 51
F.7 Sampled colour non-uniformity . 52
Bibliography . 53

Figure 1 – Layout diagram of measurement setup . 11
Figure 2 – Standard measurement positions in the display active area . 12
Figure 3 – Test pattern scaling used to define the area size of the coloured rectangles

in the active area of the display . 13
Figure 4 – Low APL loading series of red, green, blue, and white test patterns used for
basic luminance, colour, and uniformity measurements . 14
Figure 5 – Medium (top) and high (bottom) APL loading versions of CTR pattern . 15

– 4 – IEC 62341-6-1:2022 RLV © IEC 2022
Figure 6 – Standard low APL RGBCMY test pattern used for centre luminance and
colour measurements . 16
Figure 7 – Optional medium APL signal loading RGBCMY test pattern used for centre
luminance and colour measurements . 17
Figure 8 – Sequence for measuring luminance and colour at the nine standard display
positions for all coloured tile patterns . 19
Figure 9 – Colour of blackbody source at various temperatures as represented on the
CIE 1931 chromaticity diagram . 22
Figure 10 – Example of representation of the same primary colours in the CIE 1931

(left) and CIE 1976 (right) chromaticity diagrams . 26
Figure 11 – Example of range in colours produced by a given display as represented
by the CIELAB colour space . 27
Figure 12 – Example of measurement setup of power consumption . 29
Figure 13 – Example of measurement setup of power consumption with embedded
video terminal . 31
Figure A.1 – Relationship between driving signal and optical response times . 34
Figure B.1 – Example of a measurement configuration for measuring luminance current

efficiency . 36
Figure C.1 – Pattern for veiling glare frustum . 37
Figure D.1 – CIE 1931 XYZ chromaticity diagram . 40
Figure D.2 – Blackbody locus (Planckian locus) and isotemperature lines in CIE 1931
chromaticity diagram . 41
Figure E.1 – Legacy model where the independent drive electronics provide a direct
correlation between the input RGB signals and the display’s colour primaries . 42
Figure E.2 – Examples of modern drive models using multi-dimensional LUTs for RGB

(top) and multi-primary (bottom) displays . 43
Figure E.3 – Example of APL signal loading behaviour for a WRGB an RGBW display
(top) and RGB (bottom) OLED display . 46
Figure E.4 – Low APL loading test pattern with small box size (1/9 of the screen size
dimensions) . 47
Figure E.5 – APL Signal loading profiles for several input colours measured at the
centre of the test pattern using Figure E.4 Figure 8. 49
Figure F.1 – Example of simple 4 % white window pattern at the centre of the screen . 51

Table 1 – Standard digital-equivalent input signals for rendering the white, primary
and secondary colours in test patterns . 17
Table 2 – Example of luminance measured for the same colour at the standard nine
screen positions and the resulting luminance non-uniformity . 19
Table 3 – Example of the same colour measured at the nine standard screen positions

and the resulting chromaticity non-uniformity . 20
Table 4 – Scaling the size of the colour boxes in the APL loading pattern relative to the
screen dimensions . 24
Table 5 – Example of a module power consumption measurements summary sheet . 30
Table 6 – Example of module power consumption measurements with contents. 32
Table 7 – Example of module power consumption measurements with images . 32
Table D.1 – x , y , A and t for Formula(D.3) and Formula (D.4) . 39
e e i i
Table E.1 – Example of luminance data for an RGB display and WRGB an RGBW
OLED display . 44

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ORGANIC LIGHT EMITTING DIODE (OLED) DISPLAYS –

Part 6-1: Measuring methods of optical and electro-optical parameters

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made to
the previous edition IEC 62341-6-1:2017. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.

– 6 – IEC 62341-6-1:2022 RLV © IEC 2022
IEC 62341-6-1 has been prepared by IEC technical committee 110: Electronic display devices.
It is an International Standard.
This third edition cancels and replaces the second edition published in 2017. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) measuring methods for power consumption of displays that have an embedded video
connection terminal are added;
b) the contents description including video signal for power consumption is modified.
The text of this International Standard is based on the following documents:
Draft Report on voting
110/1454/FDIS 110/1471/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all the parts in the IEC 62341 series, under the general title Organic light emitting diode
(OLED) displays, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

ORGANIC LIGHT EMITTING DIODE (OLED) DISPLAYS –

Part 6-1: Measuring methods of optical and electro-optical parameters

1 Scope
This part of IEC 62341 specifies the standard measuring conditions and measuring methods
for determining the optical and electro-optical parameters of organic light emitting diode (OLED)
display modules, and where specified, OLED display panels. These methods are limited to flat
displays measured in a dark room.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-845, International Electrotechnical Vocabulary – Part 850: Lighting (available at
www.electropedia.org)
IEC 61966-2-1, Multimedia systems and equipment – Colour measurement and management –
Part 2-1: Colour management – Default RGB colour space – sRGB
IEC 62341-1-2, Organic light emitting diode (OLED) displays – Part 1-2: Terminology and letter
symbols
IEC 62341-6-2:2015, Organic light emitting diode (OLED) displays – Part 6-2: Measuring
methods of visual quality and ambient performance
IEC 62087-3, Audio, video, and related equipment – Determination of power consumption –
Part 3: Television sets
rd
CIE 15:2004, Colorimetry, 3 edition
CIE S 014-1, Colorimetry – Part 1: CIE Standard Colorimetric Observers
3 Terms, definitions, and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-845,
IEC 62341-1-2, and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org
• ISO Online browsing platform: available at https://www.iso.org/obp

– 8 – IEC 62341-6-1:2022 RLV © IEC 2022
3.1.1
signal pixel
smallest encoded picture element in the input image
3.1.2
pre-gamma average picture level
average input level of all signal pixels relative to an equivalent white pixel driven by a digital
RGB input
Note 1 to entry: Unless otherwise stated, the pre-gamma average picture level (APL) will simply be referred to as
average picture level in this document.
Note 2 to entry: The APL will normally be expressed as a percentage, where a full white screen at maximum drive
level would be 100 % APL.
3.1.3
average luminance level
ALL
average luminance of the input signal on all pixels
Note 1 to entry: ALL, which is calculated by averaging of post-gamma signal pixels, is also called as the post-
gamma APL.
3.2 Abbreviated terms
ALL average luminance level
APL average picture level
CCT correlated colour temperature
CIE Commission Internationale de L’Eclairage (International Commission on
Illumination)
CIELAB CIE 1976 (L*a*b*) colour space
CMY cyan, magenta, and yellow
DRCR dark room contrast ratio
DUT device under test
eDP embedded display port
LMD light measuring device
LUT look-up table
MIPI mobile industry processor interface
PMOLED passive matrix organic light-emitting diode
RGB red, green, and blue
RGBCMY red, green, blue, cyan, magenta, and yellow
SPD spectral power distribution
sRGB standard RGB colour space as defined in IEC 61966-2-1
TCON timing controller
UCS uniform chromaticity scale
WRGB white, red, green, and blue
4 Structure of measuring equipment
The system diagrams and/or operating conditions of the measuring equipment shall comply with
the structure specified in each item.

5 Standard measuring conditions
5.1 Standard measuring environmental conditions
Measurements shall be carried out under the standard environmental conditions as follows:
– temperature: 25 ºC ± 3 ºC
– relative humidity: 25 % RH to 85 % RH
– atmospheric pressure: 86 kPa to 106 kPa
When different environmental conditions are used, they shall be noted in the report.
5.2 Standard measuring dark room conditions
The luminance contribution from unwanted background illumination reflected off the test display
shall be less than 1/20 of the display’s black state luminance. If these conditions are not
satisfied, then background subtraction is required, and it shall be noted in the test report. In
addition, if the sensitivity of the LMD is inadequate to measure 1/20 of the black level, then the
lower limit of the LMD shall be noted in the test report.
5.3 Standard setup conditions
5.3.1 General
Standard setup conditions are given below in 5.3.2, 5.3.3 and 5.3.4. Any deviations from these
conditions shall be recorded reported.
5.3.2 Adjustment of OLED display modules
The display shall be measured at its factory default settings. If other settings are used, they
shall be noted in the test report. These settings shall be held constant for all measurements,
unless stated otherwise. It is important, however, to make sure that not only the adjustments
are kept constant, but also that the resulting physical quantities remain constant during the
measurement. This is not automatically the case because of, for example, warm-up effects.
5.3.3 Starting conditions of measurements
Measurements shall be started after the OLED displays and measuring instruments achieve
stability. It is recommended that, when the display is first turned on, it be operated for at least
30 min with a loop of colour patterns rendered on the screen. Sufficient warm-up time has been
achieved when the luminance of the test feature to be measured varies by less than ±3 % over
the entire measurement method for a given display image.
5.3.4 Measuring equipment requirements
5.3.4.1 General conditions
Light measurements shall generally be made in terms of photometric or colorimetric units for a
CIE 1931 standard colorimetric observer as defined in CIE S 014-1. Luminance can be
measured by a photometer, and CIE tristimulus values (X, Y, Z) or CIE chromaticity coordinates
by a colorimeter. A spectroradiometer can also obtain photometric and colorimetric values
through a numerical conversion of the measured spectral radiance data (see for example [1] ).
A non-contact LMD, where the LMD is not in direct contact with the screen, shall be used without
an illumination source. The following requirements are given for these instruments:
a) The LMD shall be a luminance meter, colorimeter, or a spectroradiometer. The
spectroradiometer shall be capable of measuring spectral radiance over at least the 380 nm
___________
Numbers in square brackets refer to the Bibliography.

– 10 – IEC 62341-6-1:2022 RLV © IEC 2022
to 780 nm spectral wavelength range, with a maximum bandwidth of 10 nm for smooth
broadband spectra. For OLED primaries with a bandwidth ≤ 25 nm, the maximum bandwidth
shall be ≤ 5 nm. The spectral bandwidth of the spectroradiometer shall be an integer multiple
of the sampling interval. For example, a 5 nm sampling interval can be used for a 5 nm or
10 nm bandwidth.
Care shall be taken to Ensure that the LMD has enough sensitivity and dynamic range to
perform the required task. The measured LMD signal shall be at least ten times greater than
the dark level (noise floor) of the LMD, and no greater than 85 % of the saturation level.
b) The LMD shall be focused on the image plane of the display and generally aligned
perpendicularly to the display surface at the centre of the measurement field, unless stated
otherwise.
c) The relative uncertainty and repeatability of all the measuring devices shall be maintained
by following the instrument supplier’s recommended calibration schedule.
d) The LMD integration time shall be an integer number of frame periods, synchronized to the
frame rate, or the integration time shall be greater than one hundred frame periods.
e) If LMD measurements are taken for displays with impulse driving or duty driving, the high
peak luminance of these displays can cause detector saturation errors. The accuracy of
these measurements can be checked by attenuating the light with a neutral-density filter. If
the change in signal amplitude of the detector is proportional to the transmittance of the
neutral-density filter, then there are no detector saturation errors. This method is for
measuring the maximum time-averaged full-screen luminance.
When using LMDs, stray light within the LMD (e.g. lens flare, veiling glare), and non-uniformities
of sensitivity across detector area should be considered. Also, when measuring black regions,
stray light from adjacent bright regions of the displays can introduce significant errors. The stray
light can be significantly reduced by using a frustum (see Annex C).
In addition to LMDs that form an average value for the measured quantity over the measurement
field under consideration (i.e. spot photometers, see Figure 1), there are imaging LMDs which
give a value (or an array of values, e.g. R, G and B) for each individual area-element on the
DUT. Such LMDs can replace a sequential mechanical scan of the surface of a display by an
image of the entire active area of the DUT, and a subsequent evaluation of the data.
When imaging LMDs are used, a flat-field correction shall be applied to the LMD at the
measuring distance.
Acceptance area (entrance pupil)
Field of view
Luminance
Angular field
Angular
meter with
of view
aperture
viewport
Measurement
field
Measurement field angle
Focus on object
being measured
IEC
Figure 1 – Layout diagram of measurement setup
5.3.4.2 High pixel count matrix displays (≥ 320 pixels × 240 pixels)
The following applies for high pixel count matrix displays:
a) When measuring matrix displays, the light-measuring devices should be set to a
measurement field that includes more than 500 pixels. For LMDs with a circular
measurement field, this would be equivalent to a disk with a diameter greater than 25 display
pixels. If smaller measurement areas are necessary, photometric and colorimetric
equivalence to 500 pixels shall be confirmed and noted in the test report.
b) For small displays, the recommended measuring distance is between 20 cm to 50 cm. For
larger displays, the measurement area shall contain at least 500 pixels. The measurement
area contains at least 500 pixels. The measuring distance shall be noted in the report.
c) The angular aperture shall be less than or equal to 5°, and the measurement field angle
shall be less than or equal to 2° (see Figure 1).
d) The display shall be operated at its design field frequency. When using separate driving
signal equipment to operate a panel, the drive conditions shall be noted in the report.

– 12 – IEC 62341-6-1:2022 RLV © IEC 2022
5.3.4.3 Low pixel count matrix displays (< 320 pixels × 240 pixels) and segmented
displays
The following applies for low pixel count matrix displays:
a) Low pixel count displays may can contain fewer than 500 pixels. When the number of pixels
in the measurement field is less than 500, it shall be noted in the report. The angular
aperture shall be less than or equal to 5°, and the measurement field angle shall be less
than or equal to 2°. The measuring conditions used shall be recorded.
b) For segment displays, the angular aperture shall be less than or equal to 5°, and the
measurement field angle shall be less than or equal to 2°. All measurements shall be
performed at the centre of a segment with the measurement field completely contained
within the segment.
c) For small displays, the recommended measuring distance is between 20 cm to 50 cm. For
larger displays, follow the manufacturer’s recommended viewing distance. For larger
displays, the measurement area shall contain at least 500 pixels. The measuring distance
shall be noted in the report.
5.4 Standard locations of measurement field
Luminance, spectral distribution and/or tristimulus measurements may be taken at several
specified positions on the display surface. The standard measurement locations are identified
by positions P to P in the active area, as illustrated in Figure 2. The active screen area is
1 9
divided into nine equal-sized boxes, with the measurement area centred within each box and
identified by the corresponding numbering shown in Figure 2. Each box is 1/3 of the width (W)
and height (H) of the active area. Centre screen measurements are taken at position P The
.
display or detector shall be translated in the horizontal and vertical directions to perform
measurements at the desired display positions, with all measurements taken normal to the
screen. Any deviation from the standard positions above shall be recorded.

Figure 2 – Standard measurement positions in the display active area
5.5 Standard test patterns
The characterization of display luminance and colour can depend on the display test pattern.
Therefore, several standard test patterns are given to help make the measurements more
realistic to actual use cases (see Annex E). Additional test patterns may also be used (see
Annex F). The standard test patterns use the scaling illustrated in Figure 3. The display is
divided into a 3 × 3 array of rectangular areas, each of which has sides that are 1/3 of the
dimension of the height and width of the screen active area. Each of these nine rectangular
areas can then be further subdivided into smaller rectangles, as demonstrated in the upper left-

hand corner of Figure 3 . The smallest subdivision would yield a rectangular box that has
dimensions of 1/9 of those of the active area of each region of the 3 × 3 array.

Figure 3 – Test pattern scaling used to define the area size of
the coloured rectangles in the active area of the display
The standard test pattern for basic primary luminance and colour measurements shall use the
low APL loading example of the colour tile test patterns illustrated in Figure 4. In this case,
coloured rectangular boxes, with 1/9 of the dimensions of the active area, are centred on the
nine standard active area locations on a black background. The red, green, and blue boxes are
driven at the maximum input signal levels for the primary channels. For example, the red box
is driven at the maximum input signal for the red channel, while the green and blue channels
are at their minimum signal level. The white boxes are driven at their maximum red, green, and
blue channel inputs. Each colour tile pattern is identified by the initials CT (colour tile) and the
colour of the centre box. The patterns in Figure 4 are identified as CTR, CTG, CTW, and CTB
starting at the upper left-hand pattern and moving clockwise.

– 14 – IEC 62341-6-1:2022 RLV © IEC 2022

Figure 4 – Low APL loading series of red, green, blue, and white test patterns used for
basic luminance, colour, and uniformity measurements
The area scaling of the coloured rectangles is adjusted to manipulate the APL loading on the
display. The amount of APL loading is input-referred, assuming it is an RGB digital input. The
percent APL is defined as:
N
PLi
∑
i =1
APL(%) = 100 ×
N
N
PL
∑ (1)
i
i=1
APL % 100×
( )
N
where the summation is over all pixels in the active area, PL is the normalized signal pixel level
i
th
of the i pixel relative to maximum white level, and N is the total number of pixels. A 100 %
APL would be represented by all pixels in the active area at maximum white level. This would
be implemented by setting the levels for the red, green, and blue input channels to their
maximum values. A single primary colour (e.g. red) rendered on a full screen would have 1/3 of
the APL of a full white screen. If it is assumed that the red, green, and blue areas correspond
to 1/3 of the APL of the white areas, then the APL for each pattern in Figure 4 is (starting at the
upper left-hand corner and going clockwise) 5,3 %, 5,3 %, 6,2 %, and 5,3 %. The average APL
for the four patterns in Figure 4 is 5,6 %. An example calculation of the top left pattern in
Figure 4 is given by:
[(7 primary colours × 1/3 of white) + (2 white boxes × 3 / 3 of white)]
(2)
× [(1 / 9) fractional area of boxes] = 5,3 % APL

=
Higher loading versions of the colour tile pattern are illustrated in Figure 5. The sequence of
four-colour tile patterns at the medium loading geometry would give an average APL equivalent
to 22 %, whereas the high loading pattern would give an average APL equivalent to 50 %.

NOTE The corresponding CTG, CTB, and CTW patterns are of similar size but have green, blue, and white,
respectively, in the centre box.
Figure 5 – Medium (top) and high (bottom) APL loading versions of CTR pattern
In cases where more than the white and RGB input primary colours are needed for luminance
and colour measurements, the low APL loading RBGCMY box pattern illustrated in Figure 6
shall be used. This pattern is intended for centre luminance and colour measurements. Each
coloured box is centred on the nine standard active area locations (see Figure 2) on a black
background, with height and width corresponding to 1/9 of the dimensions of the active area.
Each of the white, red, green, blue, cyan, magenta, and yellow colours are at their maximum
input-referred signal setting as defined in Table 1. The centre rectangle can be changed to the
desired colour to be measured. However, the colours of the surrounding eight rectangular
patterns shall remain constant. If a maximum white colour is rendered in the centre box, the
APL is 6,2 % for this low loading case. Additional higher-loading patterns may also be used.
For example, a medium APL loading pattern with 2/9 of the dimensions of the active area that
produces about 25 % APL is illustrated in Figure 7. A high-loading version, where each
rectangle is 1/3 of the active area's dimensions, would have 56 % APL.

– 16 – IEC 62341-6-1:2022 RLV © IEC 2022

NOTE The centre rectangle can be changed to any desired colour, while the surrounding rectangles remain fixed.
The notation identifies the colours used in the pattern and is not displayed when measurements are taken.
Figure 6 – Standard low APL RGBCMY test pattern used
for centre luminance and colour measurements

Table 1 – Standard digital-equivalent input signals for rendering
the white, primary and secondary colours in test patterns
Colour Q Equivalent 8-bit digital signal level
Red channel Green channel Blue channel
K (black) 0 0 0
R (red) 255 0 0
G (green) 0 255 0
B (blue) 0 0 255
Y (yellow) 255 255 0
M (magenta) 255 0 255
C (cyan) 0 255 255
W (white) 255 255 255
NOTE The centre rectangle can be changed to any desired colour, while the surrounding rectangles remain fixed.
Figure 7 – Optional medium APL signal loading RGBCMY test pattern used
for centre luminance and colour measurements
A more detailed evaluation of APL loading can be performed by starting with the low APL test
pattern in Figure 6, but the size of all boxes increases gradually until the entire screen is filled.
The colour pattern of each box location remains the same, only the size of each box changes.

– 18 – IEC 62341-6-1:2022 RLV © IEC 2022
6 Measuring methods for optical parameters
6.1 Primary l
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